Repeatable technology opens up the possibility that the method can be automated and single-atom transistors could be manufactured, according to the group at the University of New South Wales. Single-atom transistor built with precise control article tells that the lab members used a scanning tunneling microscope to manipulate atoms at the surface of a silicon crystal. Then with a lithographic process, they laid phosphorous atoms onto the silicon substrate.

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Tomi Engdahl says:

IBM is announcing today that it has made major advances toward creating a practical, full-scale quantum computer, a fabled, theoretical machine that relies on the tiniest atomic properties to compute problems faster than any supercomputer that exists today.

Scientists at IBM Research in Yorktown Heights, N.Y., said that their quantum computing solution leverages the underlying quantum mechanics of matter and that a real quantum computer, which could work on millions of computations at once, could be built in the next decade. The hugely multitasking devices will have big implications for fields such as data encryption.

In classical computers, the basic piece of information is a bit. A bit can have only one of two values:: “1″ or “0″. That forms the basis for the on-off nature of digital computers, like a light switch. It is either on or off. Qubits can hold a value of “1″ or “0″ as well as both values at the same time. This feature is known as “superposition” and it lets quantum computers do millions of calculations at once.

The challenge of harnessing this power is controlling or removing quantum decoherence, or the creation of errors in calculations caused by interference from heat, electromagnetic radiation, and materials defects in a chip. Scientists have experimented with ways to reduce the errors and lengthen the period in which qubits retain their quantum mechanical properties. If the time is long enough, error correction can make it possible to perform long and complex calculations.

IBM says there’s a variety of ways to achieve the end goal of a functioning quantum computer. IBM’s group focused on using superconducting qubits — basically designer molecules — that allow easier mass production.

Tomi Engdahl says:

However, while organic molecules can be made to behave like electronic gates, it’s difficult to create repeatable connections to them without damaging the molecule.

The Taiwanese researchers claiming the breakthrough say it could help overcome a difficult hurdle in the world of organic electronics: providing a repeatable way to “connect” organic molecules to electrical signals, without degrading the molecules.

By binding to two gold nanoparticles, this “anti-nanoparticle” forms a junction that can be connected to the outside world.

When a voltage is applied to the device, the researchers say, it behaves like a transistor gate.

Tomi Engdahl says:

University of New South Wales School of Physics professor Victor Flambaum has found a method of timekeeping nearly 100 times more accurate than the best atomic clocks. By using the orbit of a neutron around an atomic nucleus he says the system stays accurate to within 1/20th of a second over billions of years.

[...] could revolutionize the way we tackle problems that stump even the best classical computers. Single atom transistor recently introduced has been seen as a tool that could lead the way to building a quantum computer. [...]

Harvard recently sent a memo to faculty saying, ‘We write to communicate an untenable situation facing the Harvard Library. Many large journal publishers have made the scholarly communication environment fiscally unsustainable and academically restrictive. This situation is exacerbated by efforts of certain publishers (called “providers”) to acquire, bundle, and increase the pricing on journals.

Physicists from Chalmers University of Technology in Sweden, led by Per Delsing, have demonstrated a new kind of detector for sound at the level of quietness of quantum mechanics.

This ushers in a new class of quantum hybrid circuits that mix acoustic elements with electrical ones

The “quantum microphone” is based on a single electron transistor, that is, a transistor where the current passes one electron at a time. The acoustic waves studied by the research team propagate over the surface of a crystalline microchip, and resemble the ripples formed on a pond when a pebble is thrown into it.

The wavelength of the sound is a mere 3 micrometers, but the detector is even smaller, and capable of rapidly sensing the acoustic waves as they pass by

The detector is sensitive to waves with peak heights of a few percent of a proton diameter, levels so quiet that sound can be governed by quantum law rather than classical mechanics, much in the same way as light.

“The experiment is done on classical acoustic waves, but it shows that we have everything in place to begin studies of proper quantum-acoustics, and nobody has attempted that before”, says Martin Gustafsson, PhD student and first author of the article.

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A new phenomenon discovered in ultracold atoms of a Bose-Einstein condensate (BEC) could offer new insight into the quantum mechanical world and be a step toward applications in “atomtronics”—the use of ultracold atoms as circuit components. Researchers at the National Institute of Standards and Technology (NIST) have reported the first observation of the “spin Hall effect” in a cloud of ultracold atoms.

The world might still be 20 years from the end of Moore’s Law, but the hunt for technologies to replace semiconductors is going on right now. A group from Michigan Technological University is offering one such alternative: a quantum tunnelling transistor that operates at room temperature.

The culmination of work begun in 2007, their demonstration has been published in Advanced Materials

Quantum properties are seen as a promising replacement for semiconductors on both scores: transistors can be built at the single-atom scale, and they don’t have the same heat dissipation issues. However, most quantum effect transistors need to function at cryogenic temperatures.

That makes room temperature operation an important goal for development – and that’s what the MTU group, led by MTU physicist Yoke Khin Yap, is claiming.

Their quantum transistor is fabricating by placing gold quantum dots on boron nitride nanotubes. The three-nanometre gold dots were placed using lasers, while the nanotubes both provide insulation between the dots, and confine the dots.